580 DR. H. DEBUS ON THE CHEMICAL THEORY OF GUNPOWDER. 
or simplified : 
4KNO s +5C=2K 2 CO s +3COa-2N 8 
and those of point C according to 
or simplified : 
16KN0 3 +24C+16S=8K a S 3 +2|pO s +8N s 
2KN0 3 +3C+2S=K 2 S 2 +3C0 2 +N 2 
if in this last equation the potassic disulphide be changed into monosulphide, then the 
equation would become identical with the old one, which for many years was supposed 
to represent the metamorphosis of all sorts of gunpowders. 
As already observed, all points within the triangle represent, by their coordinates, 
mixtures of carbon and sulphur with 16 mols. of KN0 3 , which besides carbonic acid 
and nitrogen, will yield during their combustion three potassium salts. 
The geometrical construction of the coefficients of equation (XIII.), does not only 
offer the advantage of representing by the coordinates of the points within the triangle 
B D C all possible proportions of saltpetre, carbon, and sulphur which can transform 
themselves into potassic carbonate, potassic sulphate, potassic disulphide, carbonic acid 
and nitrogen, but it also enables us to deduce at once, geometrically, the quantities of 
these products of combustion. 
If we desire to know the composition of all those mixtures which shall contain 
variable quantities of carbon and sulphur, but shall all produce by their combustion 
the same amount of potassic carbonate, we can deduce the answer from the following 
considerations : 
For such mixtures the coefficient of the potassic carbonate in equation (XIII.) must 
assume a constant value. Hence, 
and 
64-f-8y— I6z=c. 
y=2z+ 
c—64 
8 
the equation of a line parallel to the side B C of the triangle. The coordinates of the 
points of such a line indicate the composition of mixtures which will burn with pro¬ 
duction of the same amount of potassic carbonate. The amount of potassic carbonate 
is constant for each parallel line, but changes from one line to another. Now as they 
intersect the lines B D and D C, it is only necessary to ascertain the amounts of 
potassic carbonate corresponding to the points of one of these sides in order to know 
the amount of potassic carbonate formed by the combustion of a mixture represented 
by the coordinates of any point within the triangle. 
Similar considerations lead to the equation : 
320—c 
16 
